Posted by Lee T. on Friday, 29 August 2014, at 12:35 p.m., in response to Re: help with marking, posted by Jim Meredith on Friday, 29 August 2014, at 12:16 p.m.

I immediately thought of Fork Union when I read about the F-U marking. My dad was a cadet there in the 1930's and graduated in 1937. He told me their training / drill arms were exclusively the M1903, except for the BAR on the range, and never mentioned the trapdoor. But that doesn't preclude the possibility of an earlier use. Also, through many years of communications with the school, reunions and letters from classmates up until his death in 2001, most regarding conditions and history of the school, I never saw any reference to the school that wasn't FUMA - Fork Union Military Academy. Never once saw it as 'F-U'. Again, doesn't mean it couldn't have been used earlier.